If you are like many new iPhone 5 buyers you have already started scouring eBay to find a deal on Apple’s new Lightning cable or adapter. If you do a search you come up with hundreds of U.S. vendors offering you a pre-order of the new cable and adapter with prices ranging from $8.40 to $39.90. Keep in mind the cable is available directly from Apple for $19.00 and that adapter for $29.00. Yes, very overpriced.

The issue is, these devices are adaptive. Meaning they can change what pins information and power is transmitted on. Unless these companies can reverse engineer the chip, make a reliable copy at a cost worth competing a lot of people are putting up money for a product that may never be delivered.

Here is a rundown from 9to5Mac on the issue.

-Lightning is adaptive.

-All 8 pins are used for signals, and all or most can be switched to be used for power.

-The outer plug shell is used as ground reference and connected to the device shell.

-At least one (probably at most two) of the pins is used for detecting what sort of plug is plugged in.

-All plugs have to contain a controller/driver chip to implement the “adaptive” thing.

-The device watches for a momentary short on all pins (by the leading edge of the plug) to detect plug insertion/removal.

-The pins on the plug are deactivated until after the plug is fully inserted, when a wake-up signal on one of the pins cues the chip inside the plug. This avoids any shorting hazard while the plug isn’t inside the connector.

-The controller/driver chip tells the device what type it is, and for cases like the Lightning-to-USB cable whether a charger (that sends power) or a device (that needs power) is on the other end.

-The device can then switch the other pins between the SoC’s data lines or the power circuitry, as needed in each case.

-Once everything is properly set up, the controller/driver chip gets digital signals from the SoC and converts them – via serial/parallel, ADC/DAC, differential drivers or whatever to whatever is needed by the interface on the other end of the adapter or cable. It could even re-encode these signals to some other format to use fewer wires, gain noise-immunity or whatever, and re-decode them on the other end; it’s all flexible. It could even convert to optical.

 

For now, if you need a cable I suggest you get it from Apple. Don’t get burned by all the promises for cheaper cables being available for pre-order.